Communication interface to data networks

Abstract

This invention relates to a communications method and device which will allow a telephone connected to the Public Switch Telephone Network (PSTN) through a switching device such as a Private Branch Exchange (PBX) to transfer data between the PSTN and a closed loop digital data network. A network interface microcontroller is installed in an analog or digital telephone connected to a closed loop digital data network. The microcontroller converts the digital network data into a form suitable for transmission through the PBX to the PSTN and converts data received from the PSTN through though PBX into the digital network protocol.

What is claimed is: 
     
       1. Apparatus for transmitting data and voice signals between a digital network and a public switched telephone network (PSTN) comprising: a telephone connected to the PSTN by a PBX; and   a network interface microcontroller in the telephone for connecting the telephone to the digital network, for converting signals from the digital network into a form suitable for transmission through the PBX to the PSTN, and for converting signals received from the PSTN through the PBX into a form suitable for transmission to the digital network.   
     
     
       2. Apparatus as in claim 1, wherein: the telephone is a digital telephone.   
     
     
       3. Apparatus as in claim 1, wherein: the telephone is an analog telephone.